A new ammonite and coccolith fauna from the lowermost Fernie Formation (Hettangian) in northwestern Alberta, Canada

The occurrence of the ammonite Discamphiceras cf. silberlingi Guex in a cor e 25 cm above the base of dark, bituminous shales of the lowermost Fernie F ormation in the subsurface of northwestern Alberta establishes their middle to late Hettangian age. Associated coccoliths suggest a possible late Hett angian to early Sinemurian age, which is the oldest so far assigned to thes e shales and differs considerably from both the Sinemurian age of the type Nordegg Member of the outcrop belt and the Pliensbachian age of its suppose d basinal equivalents ("Nordegg Member" of some recent authors).